Technical Field
The present invention relates to a device for dosing a fill product into a container to be filled, preferably for dosing a viscous and/or paste-like fill product such as, for example, cream, yogurt, jam, ketchup, mayonnaise and/or baby food.
Related Art
Devices using a rotary-type process for dosing fill products into containers to be filled are known. A plurality of dosing units are generally provided around the periphery of a product reservoir, each of the dosing units having a dosing cylinder within which a dosing piston is displaceably disposed.
In the dosing units, the fill product held in the product reservoir is sucked into the dosing cylinder by means of the dosing piston. The volume sucked in is then expelled from a fill product outlet into the container below that is to be filled. Dosing of a precise volume is thereby achieved by means of the positively guided movement within the dosing cylinder of the dosing piston, which alternately sucks fill product from the product reservoir and then pushes it via a product outlet aperture into the container to be filled.
Appropriate switching between the paths that convey the product—i.e., a product channel between the dosing cylinder and the product reservoir, and an ejection channel between the dosing cylinder and the ejection aperture—is achieved in each case by means of valves. For this purpose, horizontal rotary slides, vertical rotary valves, check valves or seat valves are for example used.
FR 2 851 764 A1 discloses a device with a product reservoir upon which are mounted dosing units. The dosing units include a dosing cylinder disposed on the periphery of the product reservoir, within which a cam-controlled dosing piston is guided and which has two pneumatically controlled valves. The first valve, which is configured as an intake valve, is positioned between the dosing cylinder and the outlet valve, and switches the product channel from the product reservoir into the dosing cylinder. The intake valve is embodied as a seat valve, and can be opened and closed in a radial direction. The outlet valve is disposed below the intake valve in the axial direction of the dosing cylinder, and substantially includes a double-acting pneumatic cylinder, through which the fill product is conveyed when it is ejected.
Known arrangements, in which a radially actuated seat valve connects the product reservoir with the dosing cylinder, cannot achieve adequate ventilation of the underside of the dosing piston, with the result that a high degree of accuracy in filling cannot be achieved due to the compressible air cushion that is present in the dosing cylinder. Furthermore, emptying the product reservoir at the end of the filling procedure presents a problem.